Reducing the border area of a device

ABSTRACT

A circuit panel of an electronic device is disclosed. The circuit panel includes a substantially flat surface including an active area of the electronic device; a bent border area contiguous with and extending from the active area of the substantially flat surface; and a plurality of traces coupled to the active area and routed in the bent border area.

This application is a continuation of U.S. patent application Ser. No.15/940,580, filed Mar. 29, 2018, which is a continuation of U.S. patentapplication Ser. No. 15/591,987, filed May 10, 2017, now U.S. Pat. No.9,933,875, which is a continuation of U.S. patent application Ser. No.14/445,849, filed Jul. 29, 2014, now U.S. Pat. No. 9,652,096, which is acontinuation of U.S. patent application Ser. No. 13/229,120, filed Sep.9, 2011, now U.S. Pat. No. 8,804,347, all of which are herebyincorporated by reference herein in their entireties.

FIELD

This relates generally to the fabrication of an electronic device, andmore particularly, to bending one or more edges of a touch sensor paneland/or a display panel of an electronic device to reduce thenon-interactive border area of the device.

BACKGROUND

In recent years, mobile electronic devices have become hugely populardue to their portability, versatility, and ease-of-use. Although thereare many different types of mobile electronic devices, such as smartphones, portable music/video players, and tablet personal computers(PCs) currently available on the market, most of them share some basiccomponents. In particular, touch sensor panels, touch screens, and thelike have become available as input devices for various mobileelectronic devices. Touch screens, in particular, are becomingincreasingly popular because of their ease and versatility of operationas well as their declining price. Touch screens can include a touchsensor panel, which can be a clear panel with a touch-sensitive surface,and a display device, such as an LCD panel or an OLED panel, that can bepositioned partially or fully behind the touch sensor panel so that thetouch-sensitive surface can cover at least a portion of the viewablearea of the display device.

Given that the size of a typical mobile electronic device is relativelysmall compared to a laptop or desktop computer, it is often desirable tomaximize the display area of mobile electronic devices to increase theiruser-friendliness. For devices with a touch screen, an increased displayarea can also provide a larger touch-active area. Typically, thedisplay/touch-active area of a mobile electronic device is enclosedpartially or fully by a border area. This border area is often reservedfor routing signals from the display and/or touch sensor panel to thecircuitry of the device. Although the border area in some touch-baseddevices may already be relatively small compared to thedisplay/touch-active area, further reducing the border area wouldnevertheless help maximizing the space available for thedisplay/touch-active area of the device without increasing the overallsize of the device.

SUMMARY

This relates to methods and systems for reducing the border areas of anelectronic device so as to maximize the display/interactive touch areasof the device. In particular, a flexible substrate can be used tofabricate the display panel and/or the touch sensor panel (referred tocollectively herein as a “circuit panel”) of a mobile electronic deviceso that the edges of the display panel and/or the touch sensor panel canbe bent. Bending the edges can reduce the width (or length) of thepanel, which in turn can allow the overall device to be narrower withoutreducing the display/touch-active area of the device. Alternatively, thedisplay/touch-active area of the device can be widened withoutincreasing the overall size of the device. In some embodiments, as willbe discussed in detail below, the flexible substrate can be patternedwith perforations or made thinner at certain areas during themanufacturing process to reduce the residual stress when the flexiblesubstrate is bent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a conventional mobile electronic device with a touchscreen display.

FIG. 2 is a side view illustrating the various layers of an exemplarytouch screen display, such as the one in the device of FIG. 1.

FIG. 3 provides a top view of the exemplary touch sensor panel of FIG.2.

FIG. 4 provides a magnified view of a section of the exemplary touchsensor panel of FIG. 3.

FIG. 5 illustrates a touch sensor panel with bent border areas accordingto embodiments of the disclosure.

FIG. 6 provides a closer view of the bent border areas of the touchsensor panel of FIG. 5 according to embodiments of the disclosure.

FIG. 7 is a flow chart illustrating an exemplary process ofmanufacturing a touch sensor panel according to embodiments of thedisclosure.

FIG. 8 illustrates an exemplary touch sensor panel with bent borderareas according to embodiments of the disclosure.

FIG. 9a illustrates an exemplary digital media player having a touchsensor panel with bent border areas and fabricated according toembodiments of the disclosure.

FIG. 9b illustrates an exemplary mobile telephone having a touch sensorpanel with bent border areas and fabricated according to embodiments ofthe disclosure.

FIG. 9c illustrates an exemplary mobile computer having a touch sensorpanel with bent border areas and fabricated according to embodiments ofthe disclosure.

FIG. 9d illustrates an exemplary desktop computer having a touch sensorpanel with bent border areas and fabricated according to embodiments ofthe disclosure.

FIG. 10 illustrates an exemplary computing system including a touchsensor panel fabricated according to embodiments of the disclosure.

DETAILED DESCRIPTION

In the following description of preferred embodiments, reference is madeto the accompanying drawings which form a part hereof, and in which itis shown by way of illustration specific embodiments in which thedisclosure can be practiced. It is to be understood that otherembodiments can be used and structural changes can be made withoutdeparting from the scope of the embodiments of this disclosure.

This relates to methods and systems for reducing the border areas of anelectronic device so as to maximize the display/interactive touch areasof the device. In particular, a flexible substrate can be used tofabricate the display panel and/or the touch sensor panel (referred tocollectively herein as a “circuit panel”) of a mobile electronic deviceso that the edges of the display panel and/or the touch sensor panel canbe bent. Bending the edges can reduce the width (or length) of thepanel, which in turn can allow the overall device to be narrower withoutreducing the display/touch-active area of the device. Alternatively, thedisplay/touch-active area of the device can be widened withoutincreasing the overall size of the device. In some embodiments, as willbe discussed in detail below, the flexible substrate can be patternedwith perforations or made thinner at certain areas during themanufacturing process to reduce the residual stress when the flexiblesubstrate is bent.

An overview of the underlying structure of a conventional mobileelectronic device is provided first in the following paragraphs beforeembodiments of the present disclosure are discussed in detail.

FIG. 1 illustrates a conventional mobile electronic device 100 with atouch screen display 102. The illustrated device 100 can be a tablet PCsuch as an iPad® by Apple Inc. of Cupertino, Calif. It should beunderstood that the device of FIG. 1 can also be other types of mobileelectronic devices, such as a smartphone or a portable music player. Asshown, the touch screen display 102 can occupy a large portion of thefront surface of the device 100. In this device, the entire touch screendisplay 102 can be touch-sensitive for detecting single or multi-touchinput from a user. The display/touch-active area will be collectivelyreferred to hereinafter as the active area 104 of the device 100.

As shown in FIG. 1, although the active area 104 can span much of thewidth of the device 100, there can still be a border area 106 on bothsides of the active area 104. The border area 106 can include the areasbetween an edge 108 of the active area 104 and the product enclosureedge 110. Depending on the specification of the device, the width of theborder areas 106 can vary. In some devices with a touch screen display,such as the one shown in FIG. 1, the border area 106 may have to be wideenough so that metal traces connecting the underlying display panel tothe processing circuitry of the device 100 can be routed within theborder area 106 and hidden from view. This can occupy valuable spacethat could otherwise be used for expanding the active area 104 of thedevice. More details regarding the routing of metal traces are providedin later paragraphs.

FIG. 2 provides a side view of the various layers of an exemplary touchscreen display, such as the one in the device of FIG. 1. The multilayerstack 200 includes a top cover glass 202 laminated to a touch substrate204 using adhesive 206 deposited on top of the touch substrate 204. Asshown in FIG. 2, the cover glass 202 can have slightly larger dimensionsthan the touch substrate 204. For example, the cover glass 202 can coversubstantially the whole front surface of the device. By comparison, thetouch substrate 204 may have a size roughly that of the display of thedevice. In other words, the length and width of the cover glass 202 canbe longer than that of the touch substrate 204, respectively.

In some embodiments, thin film layers 210, 212 can be coated on thebottom surface of the cover glass 202 and/or the bottom surface of thetouch substrate 204 separated by the touch substrate 204 and theadhesive layer 206. The two thin film layers may be patterned ITO layersthat form drive and sense lines of a capacitive touch sensor. The senselines may be formed in the thin film layer 210 coated on the bottomsurface of the top cover 202 and the drive lines may be formed in thethin film layer 212 coated on the bottom surface of the touch substrate204, or vice versa. In some embodiments, by putting the drive and senselines on different surfaces of the touch substrate 204, the touchsubstrate 204 can become a capacitive touch sensor panel that is capableof sensing touches on the top surface of the cover glass 202. Changes incapacitance between each crossing of a drive line and a sense line inthose thin film layers 210, 212 can be measured to determine whether atouch has occurred at certain locations on the top surface of the coverglass 202.

FIG. 3 provides a top view of the touch sensor panel 200 of FIG. 2. Asillustrated, the touch sensor panel 200 includes both conductive rows301 and columns 302 that can form a matrix of touch pixels 306 at theircrossing points. Though FIG. 3 depicts the conductive elements 301, 302in rows and columns, other configurations of conductive elements arealso possible according to various embodiments.

Referring back to FIG. 2, the multilayer stack 200 can also includeblack mask 216 (a type of cosmetic plate or covering) formed on thebottom surface of the cover glass 202 and around the outer edge of thethin film layer 210. The black mask 216 is typically opaque (though notnecessarily black) and can be used to keep the non-transparent metaltraces (not shown in FIGS. 2 and 3) beneath it hidden from view. Themetal traces can connect the drive lines or sense lines to the touchcircuitry located in another part of the device so that touch signals(i.e., capacitance measurement at the touch pixels) can be routed fromthe touch sensor panel 200 to the touch circuitry for processing. Themetal traces are discussed in more detail below in view of FIG. 4.

In some embodiments, an additional layer of AR film, shield film, or LCM218 may be formed on the bottom of the touch sensor panel 200, formedover the thin film layer 212 on the bottom surface of the touchsubstrate 204. A shield film 218 may be used to block interferingelectrical fields in the vicinity of the touch substrate 204 so that themeasured capacitance data can accurately represent the characteristicsof one or more touches detected on the top surface of the top cover 202.A LCM 218 can be used as the display of the touch screen. Because thecover glass 202, the thin film layers 210, 212, the adhesive 206, andthe touch substrate 204 can all be formed from substantially transparentmaterial, the middle part of the touch sensor panel 200 where the blackmask 226 does not reach may be substantially see-through. This can allowthe LCM display 218 underneath the touch sensor panel 200 to be visiblefrom above the top cover 202. The thin film layer (conductive rows andcolumns) 210 can extend beyond the visible area at both ends so that theend portions of the thin film layer 210 can be hidden under the blackmask 216. This is illustrated in more detail in FIG. 4 and discussed inthe paragraphs below.

FIG. 4 provides a magnified view of a section 303 of the touch sensorpanel 200 of FIG. 3. In particular, FIG. 4 illustrates that theconductive rows 402, 404 can extend beyond the edge of the active area406 indicated by dotted lines. Each of the conductive rows 402, 404 canbe connected to a metal trace 408, 410, respectively. The metal traces408, 410 can route touch signals (e.g., capacitance measurements) fromthe conductive rows 402, 404 to a touch circuitry (not shown) of thedevice for further processing. As illustrated in FIG. 4, the metaltraces 408, 410 can be routed in the border area 412 between the edge ofthe active area 406 and the product enclosure edge 414. To prevent themetal traces 408, 410 from crossing each other's path, each of traces408, 410 can be first routed in the x-direction (i.e., along the width)of the device in various length and then in parallel in the y-direction(i.e., along the length) of the device, as shown in FIG. 4. Thisrequires that the border area 412 of the device be wide enough to houseall the metal traces 408, 410. For this reason, the border area 412 cantake up a significant area on the surface of the device, especially inrelatively large devices such as tablet PCs, which typically includemore conductive rows on the underlying touch sensor panel. This in turncan negatively affect the space that can be used as the active area(i.e., the display/touch-active area) in a device with a fixed overallwidth. The same issue can be caused by the routing traces for thedisplay panel. Thus, to provide better usability, it is desirable toreduce the border area in devices such as the one shown in FIG. 1 tomaximize its active area. In other words, by narrowing the border area,the touch screen of the device can be made larger. The followingparagraphs introduce various embodiments of this disclosure that canmaximize the active area of a device without increasing its overalldimensions.

Embodiments of the present disclosure can significantly reduce thenon-interactive border areas of a mobile electronic device so that alarger area of the device surface can be used as the active area fordisplay and/or receiving touch-based input. In various embodiments, thiscan be achieved by using a flexible substrate to serve as the basesubstrate for the touch sensor panel and/or the display panel. Duringthe manufacturing process, the flexible substrate can be bent near itsedge so that the border area in which the metal traces connecting theconductive rows and/or columns to the touch circuitry are routed takeslittle, if any, space in the x-dimension (width) of the device. This inturn creates more space that can be used as the active area (e.g.,display and/or touch-active area) on the device surface. In otherembodiments, the substrate may not be flexible, but instead may beinitially formed in a bent configuration. Although the exemplaryembodiments below describe bending one or both side edges of a touchsensor panel, it should be understood that the other edges (e.g., thetop and bottom edges) of the panel can be similarly bent to increase theother dimensions of the active area. Although the embodiments describebending the border areas of a touch sensor panel in a touch screendevice, it should be understood that the same process can be applied todisplay panels built on a flexible substrate. Details of some of theseembodiments are provided in the following paragraphs in view of FIGS.5-8.

FIG. 5 illustrates a touch sensor panel 500 according to one embodimentof the disclosure. In this embodiment, the touch sensor panel 500 can befabricated using a flexible substrate such as plastic. Unlike touchsensor panels made from rigid material such as glass, the flexiblesubstrate can allow the touch sensor panel 500 to be bent during thefabrication process. For example, the non-active edges 502, 504 of thetouch sensor panel 500 of FIG. 5 can be bent at an angle ofapproximately 90 degrees. In this embodiment, metal traces (not shown inFIG. 5) connecting the conductive rows (or columns) to the touchcircuitry of the device can be routed in the “vertical” border areas502, 504 of the panel 500. In the embodiment where metal traces are onlyrouted along one side of the touch sensor panel, only one of the edgesof the panel needs to be bent.

FIG. 6 provides a closer view of one of the bent border areas 510 of thetouch sensor panel 500 of FIG. 5. As shown in FIG. 6, the touch sensorpanel can have a number of conductive rows 602, 604 patterned on itssurface. Each conductive row 602, 604 can be attached a metal trace 606,608, which can route the touch signals from the conductive row 602, 604to the touch circuitry of the device. The metal traces 606, 608 can berouted along the surface of the panel. As shown in FIG. 6, the metaltraces 606, 608 can be routed from their respective conductive rows 602,604, first horizontally in the x-direction along the flat surface of thepanel 500 until reaching the bent edge 610 of the panel 500. Preferably,the horizontal routing of the traces is minimum because this allows theactive area (indicated in dotted lines) 612 of the touch panel to extendas closely to the bent edge 610 as possible. Following the curvature ofthe bent edge 610, the traces 606, 608 can then be routed vertically inthe y-direction over the bent border area 502 of the panel 500. Asshown, the vertical routing distance can be different for each trace606, 608 so that the traces 606, 608 do not cross over each other.Finally, the metal traces 606, 608 can be routed along the edge of thetouch sensor panel in the z-direction of the panel towards the touchcircuitry (not shown).

Accordingly, most of the metal traces can be routed along the verticalborder area 502 of the panel 500 rather than the horizontal surface ofthe touch sensor panel 500. This can significantly reduce the spacebetween the edge of the active touch sensing area and the edge of thedevice. As shown in FIG. 5, almost the entire flat horizontal surface ofthe touch sensor panel 500 can be occupied by the touch-active area 506of the panel 500 for sensing touches on the device surface. In otherwords, the touch-active area 506 can reach the bent edge of the panel500. As a result, the active area of the touch sensor panel can be madelarger without increasing the overall dimension of the device.Alternatively, the device can be made smaller without reducing the touchsensing area of the touch panel.

As mentioned above, the same process can be applied to display panelsbuilt on a flexible substrate. That is, the edge of a display panel canbe bent to allow for a reduced border between the edge of the visiblearea of the display and the produce enclosure border. Traces connectingthe display to other components of the device can be routed along bentedges of the panel which no longer drives the width-dimension of thedevice.

In one embodiment, one or more perforations can be patterned along thebent edge 610 of the flexible substrate touch sensor panel to decreasethe residual stress on the panel when it is bent. In one embodiment, asillustrated in FIG. 6, perforations 614 can be formed in the areasbetween metal traces 606, 608 extending from two adjacent conductiverows 602, 604. This can allow the metal traces 606, 608 to be routedthrough the perforated bent edge region. The perforations can berectangular, as shown in FIG. 6, circular, or any other shape. Thenumber and size of each perforation can vary depending on, among otherfactors, the number and routing of the traces, the type of flexiblesubstrate used to fabricate the touch sensor panel, and the angle atwhich the panel is bent. In some embodiments, the perforations can belarge in area and low in number. In other embodiments, the perforationscan be small in area, but large in number. The pattern of perforationscan also vary in different embodiments. Preferably, the area, size, andlocation of the perforation are optimized to allow the border areas tobe easily bent without putting much stress on or breaking the underlyingsubstrate.

In another embodiment, instead of patterning perforations along the bentedge of the panel, thinning the substrate at selected areas along thebent edge can also achieve the same effect of reducing residual stresson the panel. For example, the perforated areas of FIG. 6 can simply bethinned out instead of perforated. As with perforations, the size, shapeand location of the thinned area can vary in different embodiments. Forexample, the whole bent border area can be thinned throughout.

An exemplary process for manufacturing the touch sensor panel 500 ofFIG. 6 is illustrated in the flow chart of FIG. 7. During manufacturing,first, the conductive rows or columns can be formed on one of thesurfaces of the flexible touch substrate (see reference character 700).This can be done by depositing a layer of conductive material such asITO on the flexible touch substrate and etching the ITO layer to formthe desired pattern of conductive rows or columns. Other well-knownmethods can also be applied in this step to create the desired patternof conductive rows or columns. Next, the metal traces can be formed onthe flexible touch substrate (see reference character 701). This can bedone by depositing a metal layer on top of the conductive layer andcreating a pattern of metal traces by etching or using any othersuitable method. As shown in FIG. 6 above, each of the metal traces canextend from one end of the conductive rows or columns towards to edge ofthe touch substrate. In one embodiment, all the metal traces can beparallel to each other.

In the next step, perforations can be created in a predetermined patternin an area where the touch substrate is to be bent in the subsequentoperation (see reference character 702). The perforations can be createdusing a laser, mechanical die-cut, photo-resist etch process, or anyother suitable method. In one embodiment, the perforations can becreated in the space between each pair of adjacent metal traces. Inanother embodiment, this perforating operation can be performed prior tothe conductive traces and/or metal traces being patterned. In theembodiments where the bent area is thinned rather than perforated,operation 802 can be replaced by a thinning operation performed in thesame areas of the panel.

After the perforations are created in a pattern (or the thinningoperation is performed), the non-active border area of the touchsubstrate can be bent at a predetermined angle (e.g., 90 degrees) (seereference character 703). The perforations or the thinned areas canreduce the residual stress from the bending of the panel, thuspreventing the border area from breaking off. By bending the border areaand routing the metal traces in the bent area that no longer drives thewidth dimension of the device, the border surrounding the active area ofthe touch sensor panel can be drastically reduced.

The touch substrate can then be affixed to the other layers, such as theone shown in FIG. 2, to form the complete touch screen stack.

In FIGS. 5 and 6, although the border area of the touch sensor panel 500is shown to be bent at an angle of approximately 90 degrees, it shouldbe understood that the border area can be bent at different angles inother embodiments so long as it reduces one of the dimensions (e.g.,width or length) of the overall product. For example, FIG. 8 illustratesa touch sensor panel 800 made of a flexible substrate. As shown in thefigure, the border areas 802, 804 of the panel 800 can be folded inwardstowards the back surface of the panel (i.e., bent at an angle ofapproximately 180 degrees). In some embodiments, the border areas 802,804 can wrap around and can be folded back against the back surface ofthe panel 800. This can achieve the same advantage of allowing the touchactive area of the panel to be extended closer to the edge of the deviceor reducing the overall width of the device. As in the embodimentsdiscussed above, perforations 806 can be patterned in the bent areas toreduce stress, and metal traces can be routed in between theperforations. Alternatively and additionally, the flexible substrate canbe thinned in one or more regions to make it easier to fold the borderareas.

FIG. 9a illustrates exemplary digital media player 910 that can includea touch sensor panel 915, the touch sensor panel having bent borderareas to maximize its touch-active area according to embodiments of thedisclosure.

FIG. 9b illustrates exemplary mobile telephone 920 that can include atouch sensor panel 925, the touch sensor panel having bent border areasto maximize its touch-active area according to embodiments of thedisclosure.

FIG. 9c illustrates an exemplary personal computer 944 that can includetouch sensor panel 924 and display device 930. The touch sensor panel924 can be a panel fabricated according to embodiments of thedisclosure. The display device 930 can also include a touch panelfabricated according to embodiments of the disclosure.

FIG. 9d illustrates a desktop computer 990 including a display device992. The display device 992 may include a touch panel fabricatedaccording to embodiments of the disclosure. The desktop computer 990 mayalso include a virtual keyboard 994 which incorporates a touch panelfabricated according to embodiments of the disclosure.

FIG. 10 illustrates exemplary computing system 1000 that can include oneor more touch sensor panels fabricated according to the embodiments ofthe disclosure described above. Computing system 1000 can include one ormore panel processors 1002 and peripherals 1004, and panel subsystem1006. Peripherals 1004 can include, but are not limited to, randomaccess memory (RAM) or other types of memory or storage, watchdog timersand the like. Panel subsystem 1006 can include, but is not limited to,one or more sense channels 1008, channel scan logic 1010 and driverlogic 1014. Channel scan logic 1010 can access RAM 1012, autonomouslyread data from the sense channels and provide control for the sensechannels. In addition, channel scan logic 1010 can control driver logic1014 to generate stimulation signals 1016 at various frequencies andphases that can be selectively applied to drive lines of touch sensorpanel 1024. In some embodiments, panel subsystem 1006, panel processor1002 and peripherals 1004 can be integrated into a single applicationspecific integrated circuit (ASIC).

Touch sensor panel 1024 can include a capacitive sensing medium having aplurality of drive lines and a plurality of sense lines, although othersensing media can also be used. Either or both of the drive and senselines can be coupled to a thin glass sheet according to embodiments ofthe disclosure. Each intersection of drive and sense lines can representa capacitive sensing node and can be viewed as picture element (pixel)1026, which can be particularly useful when touch sensor panel 1024 isviewed as capturing an “image” of touch. (In other words, after panelsubsystem 1006 has determined whether a touch event has been detected ateach touch sensor in the touch sensor panel, the pattern of touchsensors in the multi-touch panel at which a touch event occurred can beviewed as an “image” of touch (e.g. a pattern of fingers touching thepanel).) Each sense line of touch sensor panel 1024 can drive sensechannel 1008 (also referred to herein as an event detection anddemodulation circuit) in panel subsystem 1006.

Computing system 1000 can also include host processor 1028 for receivingoutputs from panel processor 1002 and performing actions based on theoutputs that can include, but are not limited to, moving an object suchas a cursor or pointer, scrolling or panning, adjusting controlsettings, opening a file or document, viewing a menu, making aselection, executing instructions, operating a peripheral device coupledto the host device, answering a telephone call, placing a telephonecall, terminating a telephone call, changing the volume or audiosettings, storing information related to telephone communications suchas addresses, frequently dialed numbers, received calls, missed calls,logging onto a computer or a computer network, permitting authorizedindividuals access to restricted areas of the computer or computernetwork, loading a user profile associated with a user's preferredarrangement of the computer desktop, permitting access to web content,launching a particular program, encrypting or decoding a message, and/orthe like. Host processor 1028 can also perform additional functions thatmay not be related to panel processing, and can be coupled to programstorage 1032 and display device 1030 such as an LCD panel for providinga UI to a user of the device. Display device 1030 together with touchsensor panel 1024, when located partially or entirely under the touchsensor panel, can form touch screen 1018.

Note that one or more of the functions described above can be performedby firmware stored in memory (e.g. one of the peripherals 1004 in FIG.10) and executed by panel processor 1002, or stored in program storage1032 and executed by host processor 1028. The firmware can also bestored and/or transported within any non-transitory computer-readablestorage medium for use by or in connection with an instruction executionsystem, apparatus, or device, such as a computer-based system,processor-containing system, or other system that can fetch theinstructions from the instruction execution system, apparatus, or deviceand execute the instructions. In the context of this document, a“non-transitory computer-readable storage medium” can be any medium thatcan contain or store the program for use by or in connection with theinstruction execution system, apparatus, or device. The non-transitorycomputer readable storage medium can include, but is not limited to, anelectronic, magnetic, optical, electromagnetic, infrared, orsemiconductor system, apparatus or device, a portable computer diskette(magnetic), a random access memory (RAM) (magnetic), a read-only memory(ROM) (magnetic), an erasable programmable read-only memory (EPROM)(magnetic), a portable optical disc such a CD, CD-R, CD-RW, DVD, DVD-R,or DVD-RW, or flash memory such as compact flash cards, secured digitalcards, USB memory devices, memory sticks, and the like.

The firmware can also be propagated within any transport medium for useby or in connection with an instruction execution system, apparatus, ordevice, such as a computer-based system, processor-containing system, orother system that can fetch the instructions from the instructionexecution system, apparatus, or device and execute the instructions. Inthe context of this document, a “transport medium” can be any mediumthat can communicate, propagate or transport the program for use by orin connection with the instruction execution system, apparatus, ordevice. The transport readable medium can include, but is not limitedto, an electronic, magnetic, optical, electromagnetic or infrared wiredor wireless propagation medium.

Although embodiments of this disclosure have been fully described withreference to the accompanying drawings, it is to be noted that variouschanges and modifications will become apparent to those skilled in theart. Such changes and modifications are to be understood as beingincluded within the scope of embodiments of this disclosure as definedby the appended claims.

What is claimed is:
 1. An electronic device, comprising: a transparentcover layer; a pixel array that displays images through the transparentcover layer; and a touch sensor that detects touch input on thetransparent cover layer, wherein the touch sensor comprises touch sensorelectrodes on a substrate having first and second curved edges.
 2. Theelectronic device defined in claim 1 wherein the transparent cover layercomprises glass.
 3. The electronic device defined in claim 1 wherein thepixel array comprises organic light-emitting diode pixels.
 4. Theelectronic device defined in claim 1 wherein the touch sensor electrodescomprise capacitive touch sensor electrodes.
 5. The electronic devicedefined in claim 4 wherein the capacitive touch sensor electrodes forman active touch area and wherein the active touch area extends to thefirst and second curved edges of the substrate.
 6. The electronic devicedefined in claim 1 further comprising an additional substrate on whichthe pixel array is located, wherein the additional substrate has thirdand fourth curved edges.
 7. The electronic device defined in claim 6wherein the third and fourth curved edges have thinned regions.
 8. Theelectronic device defined in claim 6 wherein the third and fourth curvededges have perforations.
 9. The electronic device defined in claim 1wherein the touch sensor has signal traces on at least one of the firstand second curved edges.
 10. The electronic device defined in claim 1wherein the substrate comprises a planar portion and wherein the firstand second curved edges bend behind the planar portion.
 11. Anelectronic device, comprising: an array of organic light-emitting diodepixels; a cover glass overlapping the array of organic light-emittingdiode pixels; a substrate having a flat portion and a bent edge; and anarray of capacitive touch sensor electrodes that detect touch input onthe flat portion and that extend to the bent edge of the substrate. 12.The electronic device defined in claim 11 wherein the array of organiclight-emitting diode pixels, the cover glass, the substrate, and thearray of capacitive touch sensor electrodes are laminated together. 13.The electronic device defined in claim 11 wherein the bent edge bendsbehind the flat portion.
 14. The electronic device defined in claim 11wherein the bent edge comprises perforations.
 15. The electronic devicedefined in claim 11 wherein the bent edge comprises a thinned region.16. An electronic device, comprising: a pixel array; a transparent coverlayer overlapping the pixel array; a substrate having a curved edge; anda touch sensor with drive lines and sense lines that form an activetouch area on the substrate, wherein the active touch area extends tothe curved edge of the substrate.
 17. The electronic device defined inclaim 16 wherein the transparent cover layer comprises glass and thepixel array comprises organic light-emitting diode pixels.
 18. Theelectronic device defined in claim 16 wherein the pixel array, thetransparent cover layer, and the substrate are laminated together. 19.The electronic device defined in claim 16 wherein the substrate has aflat portion and wherein the curved edge bends behind the flat portion.20. The electronic device defined in claim 19 wherein the curved edge ofthe substrate has a thinned region.